Eutrombidium trigonum, (HERMANN, 1804)

Haitlinger, Ryszard, 2015, New records of Eutrombidium sorbasiensis MAAYORAL & BARRANCO, 2004 (Acari: Prostigmata: Microtrombidiidae: Eutrombidiinae) from Europe, with notes on some other Eutrombidium and their hosts, Linzer biologische Beiträge 47 (2), pp. 1337-1352 : 1339

E. trigonum ( HERMANN, 1804)

M a t e r i a l e x a m i n e d: Italy (continental), Lago Matesse n. Latino, 23 July 2005, 1 larva from undetermined Orthoptera, Rhodes, Gennadi , 26 May 2001, 4 larvae, Lindos, 26 May 2004, 2 larvae, all from undetermined Acrididae ; coll. R. Haitlinger. First record from Rhodes. This species is known from almost whole Europe and Turkey, excluding Iberian Peninsula and east part of Europe ( OUDEMANS 1912, SOUTHCOTT 1993, ROBAUX 1974, WOHLTMANN et al. 1996, HAITLINGER 2004a, b, 2006, 2007a, b, c, MĄKOL & WOHLTMANN 2012, SEVSAY & KARAKURT, 2013). PAOLI (1937) mentioned from Italy E. locustarum (WALSH, 1866) later recognized as E. trigonum , also ADIL & SEVSAY (2013) mentioned this species from Turkey and measurements for all stage were given. Measurements and meristic data for larvae not differs from E. trigonum . According to SOUTHCOTT (1993) and HUSBAND & WOHLTMANN (2011) E. locustarum occurs in Canada, Mexico and USA. Recently three species: E. walshi SOUTHCOTT, 1992, E. centrale SOUTHCOTT, 1993 and E. occidentale SOUTHCOTT, 1993 were synonymized.with E. locustarum ( HUSBAND & WOHLTMANN, 2011). At the same time recognized E. locustarum as good species. In reality between E. locustarum and E. tigonum lack metrical and meristic differences ( Table 2). Also leg chaetotaxy is identical. Nevertheless, HUSBAND & WOHLTMANN (2011) uphold a decision about separateness of both species. As reason geographical isolation of both species is given; however, many mites species occur at the same time in Europe and North America: Some species have wide geographical range: for example Abrolophus aitapensis ( SOUTHCOTT, 1948) described from New Guinea was found also in Macao, Vietnam, Madagascar and Guadeloupe ( SOUTHCOTT 1948, HAITLINGER 1987a, b, 2006c, 2011). E. locustarum is doubtlessly a synonym of E. trigonum . In France six species of Eutroimbidium were found; among these five species were described based on adults: E. cadurcense ANDRE, 1931, E. canigulense ANDRE, 1931, E. distinguendum ANDRE, 1931 , E. frigidum BERLESE, 1910, and E. vandeli ANDRE, 1931. Measurements given by ROBAUX (1974) for E. trigonum from France distinctly differ according to measurements and number of normal setae on tarsus I of other European specimens ( Table 2). May be it is a larva belonging to one of above mentioned species. E. djordjevici is very similar to E. trigonum . According to SABOORI & PEȃIĆ (2006) it differs from E. trigonum in Ti I (6 normal setae vs. 5 normal setae) and Ti II (5 normal setae vs. 4 normal setae) but it is bad information. E. trigonum has also Ti I with 6 setae and Ti II with 5 setae. In remarks of E. djordjevici are mentioned 7 features differing both species: PLN, LPS, LN, PL, SL, HS/PLN and LSS/SS, however E. djordjevici has only Pl and SL slightly shorter ( Table 2). Index HS/PLN (1.94-4.26 vs.3.42-6.5), LSS/SS (2.53-3.62 vs. 2.62-3.27) is in range of variability. Other metrical data in both species are identical. Therefore, E. djordjevici is a synonym of E. trigonum .